Fuel injection nozzle construction and mounting



H. H. HAS

Aug. 4, 1959 FUEL. INJECTION NOZZLE CONSTRUCTION AND MOUNTING Filed May 18, 1956 /.///////`////////////////////////////r//rrrrrrr//r/v INVENTOR BY fla/'7' //af ATTOR NEWS United States Patent() f FUEL INJECTION NOZZLE CONSTRUCTION AND MOUNTING Herbert H. Haas, Royal Oak, Mich., assignor, by mesne assignments, to Continental Motors Corporation, Muskegon, Mich., a corporation of Virginia Application May 18, 1956, Serial No. 585,720

19 Claims. (Cl. 12S-32) This invention relates to fuel injection type internal combustion engines and more particularly to the mounting and assembly of a fuel injection nozzle in the engine cylinderhead.

In certain types of fuel injection engines it is required that the fuel injection nozzle be mounted'through the cylinder head in the area occupied by the rocker box housing so that the nozzle tip may protrude into the combustion cylinder intermediate the intake and exhaust valves.

Since the cylinder head in the area of the valves is necessarily relatively thick and, particularly with aircooled engines, it is difficult to sufficiently cool the head in this area, the problem of cooling the nozzle arises. This problem specifically is covered in applicants copending application 585,639 led May 18, 1956, entitled Injection Nozzle Cooling, now Patent 2,858,813, issued November 4, 1958. Butlthe adaptation of the nozzle to the cooling means there described, presents additional problems in the mounting and supporting of the nozzle, for which the present invention provides. The injection nozzle protrudes through the rocker box housing, and the problem of isolating the injector mechanism and the cooling air from the oil in the interior of the housing arises.` Heretofore injection nozzles have l'been installed within the rocker box housing, but this necessitates dismantling the rocker box cover to gain access to the nozzle, and in addition, presents the problem of providing a passage for the fuel injection lines. Also, it is necessary to mount the vnozzle assembly of steel construction, in an aluminum cylinder head, in which case problems of diierent thermal expansion coefficient arise. All of these factors are generally related, and the construction of the present invention is such as to take them all into consideration.

. A .particular object of the present invention is to solve the problem of mounting an injection nozzle through a rocker box housing into a cylinder head structure, where an annular cooling air passage must be provided around the injection nozzle, by providing a means for retaining the injection nozzle in substantially rigid axial alignment, which means is adapted to compensate for differences of thermal expansion between the parts of the cylinder head and injection nozzle.

A further object of the invention is to provide an improved rocker box housing and injection nozzle assembly by constructing a nozzle assembly which protrudes through the rocker box cover, having the fuel injection line connection exterior of the rocker box housing and being easily removed without dismantling other cylinder and rocker box components.

' Another object of the invention is to provide for mounting of an injection nozzle through a rocker box housing into a cylinder head by constructing a sleeve member to enclose the nozzle assembly and to act as a means for retaining the nozzle in the cylinder head.

Another object of the invention is to provide for secure mounting of an injector nozzle in an aluminum cylinder 2,897,800 Patented Aug. 4, 1959 retain the nozzle in proper alignment, and so adaptedl tothe cylinder head as not to become loose or to displace the nozzle as a result of differences of thermal expansion.

For a more detailed understanding of the invention reference may be made to the accompanying drawing illustrating a preferred embodiment of the invention in which like characters refer to like parts throughout the several views and in which- Fig. l is a fragmentary cross-section of a cylinder head adapted in accordance with the present invention to retain a fuel injection nozzle.

Fig. 2 is a fragmentary cross-section illustrating a modication of the structure shown in Fig. l, and

, Fig. 3 is a section taken substantially on the line 3-3 of Fig. 1.

v.A portion of cylinder head structure 10, preferably of aluminum, is illustrated as having a combustion chamber 11, an air intake passage 12 and an exhaust passage 13 opening into the combustion chamber 11 and having intake valve 14 and exhaust valve 15 respectively operable at the intake and exhaust port openings. A rocker box housing structure 16 is adapted to be secured to the cylinder head structure 10 by any means such as bolts 17 and is provided with an upper flanged hole 18 through cylinder head. The insert is -preferably made of a material having certain characteristics, viz., it should not be too different from aluminum to maintain a good bond with lthe aluminum cylinder head 10, it should not be too different gfrorn steel so as to reduce the difference in thermal expansion between the insert 26 and the nozzle assembly 19 for maintaining the necessary sealing pressure between them, it should be suitable for thread connection with steel parts, and it should be heat resistant to protect the edge of the bore portion 25a in which high temperatures and occasionally fuel spray impingement may occur. The preferred material known as Ni-resist meets these qualifications.

The portion of the insert 26 lining the reduced diameter bore portion 25a, has a flange 26a coacting with annular ribs 27, for securing the insert 25 against axial displacement, and due to the fact that the coefficient of expansion of the aluminum cylinder head is greater than that of the insert 26, a section of the head at 10a, having the reduced diameter bore portion 25a and located between shoulder 25b and the combustion chamber, is held under axial compression between the main body of the insert 26 and the flange 26a as engine operating temperature increases. In addition, the iiange 26a protects the edge of the bore portion 25a as mentioned above.

The injection nozzle assembly 19 is provided with a two-part body 19a integrally secured to a nozzle holder 19b and provided with a fuel inlet fitting 30 and passage 31, a leak-oit passage 32, an injector mechanism 33, and an injector tip 33a extending into the combustion chamber 11. The injector mechanism 33 is of conventional construction and its operation does not apply to the present invention, so a detailed description is not included herein.

-The nozzle holder 19b is spaced from the inner bore I 26h of the insert 26 to provide an annular chamber.34

substantially separated into upper and lower'chamber" 3 portions '34a and 34b respectively by a nozzle body shoulder 35. A spiral finned cooling member 36 is vvsecuredto the nozzle holder 19b and occupies the lower chamber portion 34b. The purpose and operation lof the finned member 36 is described in theaforesaid patent.

A-tubular sleeve or shield 40, `preferably constructed of steel, is an integral'part of the nozzle assembly 19, being disposed only through the rocker box housingstructure 16, being preferably threaded at 41 into the insert 26, and is provided' with an annular seal 42 which fits into the hole 18 of the rocker box housing structure 16 as shown. A nut member 43 is secured to and preferably forms a part of the upper end of the sleeve 40 for use in screwing the sleeve 40 into the cylinder head bore insert 26. The nut member 43 may be an integral part of, or brazed to, thesleeve 40, asdesired.

The shield 40 serves-.several purposes, as follows: It retains the injection nozzle assembly in place, exerting the desired sealing pressure of the 'nozzle holder \19b against the lower end of the bore portion 26b. It acts as a nozzle extractor, since on removing the sleeve 40 by unscrewing, the top of the nut 43 is thrust againstl an upper nozzle shoulder 19C, thereby pulling the nozzle tip 34 out of the reduced bore portion where it may have become locked due to carbon deposits. It forms an annular passage for cooling air, as described in the aforesaid Icopending application. It seals the rocker box housing structure 16 against oil leakage by means of the seal 42. It seals the lower part of the nozzle 'against water and dust by means of an annular seal 49. Finally, it supports the upper end of the injection nozzle to prevent vibration, as shown in Fig. 3.

vIt will be seen also that a cylinder head portion b surrounding the upper part of the insert 26, is raised into the rocker box housing area. When the sleeve 40 and injector nozzle 19 are removed, the portion 10b prevents oil in the rocker lbox from draining through the bore of the insert 26 into the engine combustion chamber 11.

Between the lower end :of the sleeve-40 and the shoulder 35 of the nozzle holder 19b, in the upper chamber portion 34a is either a flat spring 44 as shown in Fig. 1 or a spacer 45 as illustrated in Fig. 2. The spring 44 or spacer 45 is preferably made of a material having substantially the same rate of expansion as the insert 26 and is therefore effective to compensate for differences in expansion while retaining the nozzle assembly 19 rigidly in place, applying suiicient force to prevent combustion chamber gas and pressure from escaping past a seal 46 located between the nozzle holder 19b and the insert 26 as shown in Fig. l. The sleeve 40 will be seen to be integrally assembled with the nozzle 19, so that the whole is removable as a unit from the rocker box housing 16. The sleeve 40 can only be disassembled from the nozzle 19 by disassembling the nozzle body 19a and the nozzle holder 19h.

A passage 47 provided in the cylinder `head passes cooling air to the lower end of the chamber 34b from any suitable source such as the intake manifold as shown if the engine is supercharged on the pressure side of the air cooling system. This air moves spirally past the member 36 to the upper chamber 34a, then around the spring 44 or through a suitable passage 48 in the spacer 45. An annular clearance is provided between the nozzle body 19a and the sleeve 40 to permit the air to bleed off from the top of the assembly to the atmosphere. A one-way seal 49 permits air to pass upward, but prevents a reverse ow, and in the case of submersible engines, prevents water or other foreign matter from getting into the chamber 34. The sleeve 40 also isolates the cooling air passages from oil in the interior of the rocker box v16.

Although but one preferred embodiment of the invention has been described herein, it will beapparent vto those skilled in the `art 'to which the invention pertains that vari- Vaziravgeoo ous changes and modifications may be made therein without departing 'from the spirit of the invention or'the scope of the appended claims.

I claim:

1. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, said cylinder head having a bore open to said combustion chamber, an insert member secured in said bore and supporting a fuel yinjection nozzle assembly, said bore and said insert member having corresponding reduced Vdiameter portions adjacent said combustion chamber, said bore thereby provided with van inner shoulder supporting said linsert member, and said insert member reduced diameter portion provided with a protective flange at the end adjacent said combustion chamber to lock the insert member to said bore reduced diameter portion.

2. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, said cylinder head having a bore open to said combustion chamber, an insert member secured in said bore and supporting a fuel injection nozzle assembly, said bore and said insert member having corresponding reduced diameter portions adjacent said combustion chamber, said bore thereby provided with an inner shoulder supporting said insert member, and said insert member reduced diameter portion provided with a protective flange .at the end adjacent said combustion chamber to lock the insert member to said bore reduced diameter portion, said insertmember constructed of a material having a lower coefficient of thermal expansion than 'that of said cylinder head material whereby the cylinder head portion immediately vsurrounding said bore reduced diameter portion will be put under compression by said insert Ymember flange as the temperatures of said cylinder head and said insert member increase.

3. yIn a .fuel `injection type internal combustion engine' having'a vcylinder head provided with a combustion chamber, said cylinder head having a bore open to said cornbustion chamber, Ian insert member secured in said bore and supporting a fuel injection nozzle assembly, said insert providing an annular chamber around said nozzle assembly,.s'aid bore and said insert member having corresponding reduced diameter portions adjacent said cornbustion chamber, said bore thereby provided with an inner shoulder supporting said insert member, and said insert member reduced diameter portion provided with a protective flange at the end adjacent said combustion chamber to lock the insert member to said bore reduced diameter portion, said insert member constructed of a material having a lower coeticient of thermal expansion than that of said cylinder head material, whereby the cylinder head portion immediately surrounding said bore reduced diameter portion will be put under compression by 'said insert member flange as the temperatures of said cylinder head and said insert member increase, said insert member material having a higher coeicient of thermal expansion than Vsaid nozzle assembly, and means disposed in said'chamber `for compensating for the difference in expansion between said insert member and said nozzle assembly.

4. In a fuel injection type internal combustion engine having a cylinder'head provided with a combustion chamber and intake and exhaust ports opening into said combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head having a bore open at one end to said combustion chamber and at the other end to the interior of said rocker box housing, a fuel injector nozzle supported in said bore and extended through said rocker box and extended beyond the upper limits of saidrocker box, a tubular sleeve encasing said injector nozzle and secured to the cylinder head, retainer means carried -by said fuel injector nozzle, said sleeve being operable upon securing same to said cylinder head to engage said retainer means and exert A m.; 4l

pressure thereon to hold said nozzle against axial displacement relative to said cylinder head, and means sealing the upper end of said sleeve with the rocker box Where said sleeve projects therethrough, and said sleeve supporting the nozzle assembly against lateral movement where said nozzle assembly projects from said rocker box.

5. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, said cylinder head having a bore open to said combustion chamber, an insert member secured in said bore integrally with said cylinder head and supporting a fuel injection nozzle assembly, said nozzle assembly comprising a nozzle holder structure spaced from said insert to provide an annular chamber between said insert and said nozzle holder structure and means disposed in said chamber for retaining said nozzle assembly against axial displacement, said means constructed and arranged to compensate for differences of axial thermal expansion between said nozzle holder structure and said insert member and being integrally assembled with said nozzle holder structure.

6. In a fuel injection'type internal combustion engine having a cylinder head provided with a combustion chamber, said cylinder head having a bore open to said combustion chamber, an insert member secured in said bore integrally with said cylinder head and supporting a fuel injection nozzle assembly, said nozzle assembly comprising a nozzle holder structure spaced from said insert to provide an annular chamber between said insert and said nozzle structure and means disposed in said chamber for retaining said nozzle assembly against axial displacement, said means constructed and arranged to compensate for differences of axial thermal expansion between said nozzle holder structure and said insert member and being integrally assembled with said nozzle holder structure, said nozzle assembly including a retaining member removably securing said nozzle assembly at one end of said insert member and annularly disposed around a portion of said nozzle holder structure, said nozzle holder structure having an annular shoulder in said chamber and axially spaced from said retaining member, and said means comprising an annular spacing member bearing against said retaining member and said shoulder and constructed of a material having a. coefficient of thermal expansion substantially the same as that of said insert member.

' 7. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, said cylinder head having a bore open to said combustion chamber, an insert member secured in said bore integrally with said cylinder head and supporting a fuel injection nozzle assembly, said nozzle assembly comprising a nozzle holder structure spaced from said insert to provide an annular chamber between said insert and said nozzle holder structure and means disposed in said chamber for retaining said nozzle assembly against axial displacement, said means constructed and arranged to compensate for diiferences of axial thermal expansion between said nozzle holder structure and said insert member `and being integrally assembled with said nozzle holder structure, said nozzle assembly including a retaining member removably securing said nozzle assembly at one end of said insert member and annularly disposed around' a portion of said nozzle holder structure, said nozzle holder structure having an annular shoulder in said chamber and axially spaced from said retaining member, and said means comprising an annular spring member bearing against said retaining member and said shoulder.

' 8. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head having a bore open at one end to said combustion chamber and at the other end to the interior of said rocker box housing, an insert member secured in said bore "integrally with said cylinder head and adapted to retain a fuel injection nozzle assembly therein, said vnozzle assembly extending through said rocker box housing, said nozzle assembly comprising a nozzle holder structure and a tubular sleeve member disposed in said housing around only the portion of said vnozzle holder structure extending through said housing and providing an annular cooling air passage around said nozzle holder structure, said nozzle holder structure extending beyond the end of said sleeve member into said bore and engaged thereby, said sleeve member isolating the air passage from the interior of said housing, said sleeve member constructed and arranged to removably secure said nozzle assembly to said insert member, and means coacting between said sleeve member and said nozzle holder structure to retain same in said insert and to compensate for differences of expansion between said insert and said nozzle assembly.

9. In a fuel injection type internal combustion engine 'having a cylinder head provided with a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head having a bore open at one end to said combustion chamber and at the other end to the interior of said rocker box housing, a fuel injection nozzle assembly supported inrsaid bore and extending through and beyond the upper limits of said rocker box housing, said nozzle assembly comprising a nozzle holder structure and a tubular sleeve member encasing the portion of said nozzle holder structure extending through said rocker box housing, said sleeve member constructed and arranged to secure said nozzle assembly to the cylinder head, and means sealing the upper end of said sleeve member with the rocker box Where said nozzle assembly projects therethrough, a source of cooling air and means communicating same with the injection nozzle assembly Within said cylinder head bore, said sleeve member bein-g radially spacedpfrom said nozle holder structure to provide a one-way vent chimney for the escape of cooling air from the interior of said injection nozzle assembly.

l0. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head having a bore open at one end to said combustion chamber and at the other end to the interior of said rocker box housing, an insert member secured in said bore integrally with said cylinder head and adapted to retain a fuel injection nozzle assembly therein, said nozzle assembly extending through said rocker box housing, said nozzle assembly comprising a nozzle holder structure and a tubular sleeve member disposed in said housing around the portion of said nozzle holder structure therein and radially spaced therefrom to provide an annular cooling air passage around said nozzle holder structure, said sleeve member isolating the air passage from the interior of said housing, a source of cooling air and means communicating same with said air passage.

l1. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head havin-g a bore open at one end to said combustion chamber and at the other end to the interior of said rocker box housing, a fuel injection'nozzle assembly supported in said bore and extending through and beyond the upper limits of said rocker box housing, said nozzle assembly comprising a nozzle holder structure .and a retaining means constructed and arranged to secure said nozzle assembly to said cylinder head and to retain said nozzle assembly in said bore, said retaining means being radially spaced from said nozzle ,assembly to provide a cooling air passage around said nozzle holder structure and to isolate said passage from the interior of said rocker box housing,`a source of cooling air and means communicating same with said air andfsaidnozzle holder structure .to extract .saidnozzle assemblyfrom said bore on removing jsaid retaining `means from said cylinder head. j 4 Y 12. .In .a fuel injection type internal combustion engine having a cylinder head vprovided with acombustionchamber, .and a rocker box housing structure secured .to said cylinder head, said cylinder head havinga bore open ,at one end to the interiorof said rocker .box housing,fa fuel injection nozzle assembly supportedinsaid borefand extending through and beyond the upper limits .of said rocker .box housing, said nozzle assembly comprising .a nozzle holder structure and a tubular sleeve member encasing only the portion of said nozzle holder structure extending through said rocker box housing, said .sleeve memberconstructed and arranged to secure said nozzle assembly to the cylinder head, said nozzleholder .structure extending beyond the lower-endfofsaidsleeve member into the bore and .engaged thereby, Sand means coacting between said sleeve member andsaid nozzle holder structure upon securing said .nozzle assembly A'to said cylinder head to resist axialdisplacement of saidnozzle holder structure,

13. In a fuel injection type internal combustion engine having a cylinder head provided with va combustion chamber, and a rocker box .housing `structure secured tosaid cylinder head, said cylinder head having a bore open at one end to the interior of said rocker box housing, a fuel injection nozzle assembly supported. in .said bore and extending through and beyond the upper -limits of said rocker box housing, said nozzle assembly Vcomprising a nozzle holder structure and a tubular sleeve -member en casing only the portion of said nozzle holder structure extending through said rocker box housing, .said sleeve member constructed and arranged to secure said nozzle assembly to the cylinder head, said nozzle holder structure extending .beyond the lower .end ofsaid sleeve member into the -bore and engaged thereby, means coacting between said sleeve member and said nozzle-holder structure upon securing said nozzle assembly to said cylinder head to resist axial displacement'of `said nozzle .holder structure, and a secondmeans coactingbetweenvsaidsleeve member and said nozzle holder structure and operable on removing said nozzle assembly'to engagefsaid nozzle holder structure and remove same from :said bore.

14. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box housing structuresecured to said cylinder head, said cylinder head having-.a bore open at one end to said combustion chamber and :at .the other end to the interior of said rocker box housing, a fuel injection nozzle assembly supported in said bore and extending through and beyond the upper limits of said rocker box housing, said nozzle :assembly comprising a nozzle holder structure and a tubular sleeve member assembled integrally therewith, said sleeve member constructed and arranged to secure said nozzle assembly vto the cylinder head, said sleeve member encasing only vthe portion of'said nozzle holder structure extending through said rocker box housing, said nozzle holder .structure extending beyond the bore and engaged thereby, and means sealing the upper end of said sleeve member with said rocker box housing where said .nozzle assembly projects therethrough.

15. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box .housing .structure secured to said head, said cylinder head .having a vbore open at one end .to said vcombustion chamber and at the other end to the interior of said rocker box housing, a fuel injection ,nozzle assembly supported in said bore and extending ythrough and beyond the upper limits of said rocker box housing, said nozzle .assembly comprising'a nozzle holder structureand va tubular sleeve member assembled integrally therewith, .said sleeve member constructed and .arranged to .secure .said .nozzle assembly only to .the cylinder head, .said .sleeve member encasing only .the portion of saidv nozzle holder structure extending through said .rocker box housing, said means sealing the upper vend of said sleeve member with said rocker box housing where said nozzle assembly projects therethrough, said `nozzle assembly including means cacting between saidl sleeve'member and .said nozzle holder structure only when said nozzle .assembly is secured by said sleeve member to said cylinder head to retain said -nozzle holder structure against axial displacement in said bore'. 16. In a fuel injection typeinternal combustion engine having a cylinder head provided with .a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head .having .a bore open at one end 'to said combustion chamberand at the other end tothe interior of said rocker box housing, a fuel injection nozzle Vassembly supported in said bore and extending through and beyond `the upper limits of .said rocker box housing, said nozzle assembly comprising a nozzle holder Vstructure and a tubular sleeve member assembled integrally therewith, said sleeve member constructed and arranged to secure said nozzle assembly only to the cylinder head, said sleeve member encasing only Vthe portion of saidnozzle holder structure extending through said rocker box housing, and means sealing the upper end of saidsleeve member with said rocker box housing where said nozzle assembly projects therethrough, said'nozzle assembly including means coacting between said sleeve member and said nozzle holder structure only when said nozzle :assembly is secured by .saidsleeve member -to said cylinder head :to retain said Anozzle holder structure .against =axial displacement in said bore, and said sleeve having means operative only upon removing said nozzle assembly rfrom .said cylinder head to coact with said nozzle `holder structure and to dislodge same from said bore.

17. Ina fuelinjection. type internal combustion engine having a cylinder head 4provided with a combustion chamber, and a rocker box housing structure secured to said lcylinderhead, .said cylinder head vhaving a bore openat .one end to. said combustion chamber and at the otherend to the interiorrofsaid :rocker box housing, an insert member secured in saidbore integrally with said cylinder head and .adapted l.to retain a fuel injection nozzle assembly therein, said nozzle .assembly extending through .said rocker boxhousing, .said nozzle vassembly comprising a nozzleholder structure .fand a tubular sleeve member disposed `in said housing around the portion of .said nozzle holder structure therein and lproviding yan annular cooling `air passage'zaround said nozzle holder structure, said sleeve member .isolating the air passage from the interior of .said housing, `said .sleevevmember constructed and arranged to .removably vsecure said ,nozzle assembly tosaid inner membenand means coacting ;between said .sleeve memberand saidznozzl'e holder structure to retain same in said insertand to compensate for, differences of expansionzbetween said insert and said nozzle assembly, said-coacting Ameans and said lsleeve member being constructed andy arranged tobe removed from :said nozzle holderstructure only upon disassembly vof same.

1'8. In .aifuel injection typefinternal ycombustion engine having a cylinder head Aprovided with/a combustion chamber, and a rocker :boxhousing structure Vsecured to said cylinder head, said Vcylinder head .having a bore open Yat one end to said combustionchamberand at the other end to the interior .of said rocker box housing, a fuel injection vnozzle assembly :supported infsaid bore and extending through and beyond the upper limits Vof said .rocker box housingsaid .nozzle assembly l.comprising ia nozzle holderstructurerand atubular sleeve member encasing theportion of saidfnozzle holder structure extending-through .said rocker .box housing, said nozzle holder structure extending .beyond fthe end of said sleeve member .into said-bore and .engaged .thereby,-.said sleeve memberconstructed vand arrangedto secure said nozzle assembly to said cylinder head, said nozzle holder strueture constructed and arranged to retain said sleeve member in assembly therewith upon removal of said nozzle assembly from said cylinder head, and said sleeve member removable Ifrom said nozzle holder structure only upon disassembly of same.

19. In a fuel injection type internal combustion engine having a cylinder head provided with a combustion chamber, and a rocker box housing structure secured to said cylinder head, said cylinder head having a bore open at one end to the interior of said rocker box hous ing, a fuel injection nozzle assembly supported in said bore and extending through and beyond the upper limits of said rocker box housing, said nozzle assembly comprising a nozzle holder structure and a tubular sleeve 15 member encasing the portion of said nozzle holder structure extending through said rocker box housing, said nozzle holder structure extending beyond the end of said sleeve member into said bore `and engaged thereby, said sleeve member constructed and arranged to secure said nozzle assembly to the cylinder head, means coacting between said sleeve member and said nozzle holder structure upon securing said nozzle assembly to said cylinder head to resist axial displacement of said nozzle holder structure, and a second means coaoting between said sleeve member and said nozzle holder structure and operable on removing said nozzle assembly to engage said nozzle holder structure and remove same from said bore, said nozzle assembly in its entirety as assembled thereupon being fully disengaged and enabled to be fully extracted from said rocker box housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,805,358 Burn May l2, 1931 2,685,870 Pielstick Aug. 10, 1954 FOREIGN PATENTS 299,635 Great Britain Nov. 1, 1928 

